Slingsby Kirby Kite
| Slingsby Kirby Kite | |
|---|---|
|
|
| Type: | Glider |
| Design country: |
Germany / Great Britain |
| Manufacturer: | |
| First flight: |
August 1935 |
| Production time: |
1935-1939 |
| Number of pieces: |
25th |
The Slingsby Type 6 (T.6) Kirby Kite is a single-seat glider from the British manufacturer Slingsby Sailplanes, Scarborough , which was developed in the 1930s.
history
development
Before the completion of the first license-built example of the Slingsby Grunau Baby 2 , the Kirby Kite was already under construction. With this new design, Slingsby wanted to offer the glider clubs in Great Britain a training aircraft that would have better flight characteristics than the Grunau Baby. For the strength calculations and aerodynamic design, Slingsby relied on the advice of appropriate experts, as although he was an experienced practitioner in the manufacture of aircraft in wood construction, his construction work had so far limited himself to the modification of existing samples.
As an improvement over the Grunau Baby, the wing span was increased from 13.57 m to 14.20 m by adding an additional rib, the profile remained unchanged. Another measure was the introduction of a gull wing for better circular flight characteristics. The Grunau Baby had straight wings without a V-position . In addition, the Kirby Kite was given a streamlined, rounded cross-section, which was a significant improvement compared to the hexagonal cross-sectional shape of the Grunau Baby.
The name component Kirby arose from the place name Kirbymoorside in Yorkshire, where the company location had been relocated. More recently the place name changed to Kirkbymoorside . The British Gliding Association wanted to hold a major competition at Sutton Bank in August 1935 , and the Kirby Kite should be ready to fly by that time. Since the Falcon and Grunau Baby were mainly built in the Slingsby workshops, work on the Kirby Kite could usually only be carried out in the evening. The time pressure was so great that even the construction drawings were not completely finished until after the deployment in Sutton Bank.
The successful first flight took place a few days before the start of the competition, where the Kirby Kite was classified in Class 1 as a high-performance glider. In the first competition flight, John C. Neilan reached the longest cross-country flight of all participants with a distance of 87 km and received the Wakefield Trophy .
With the first kites delivered, spoilers were not provided at the factory, but had to be retrofitted. Later models had a more rounded rudder unit with a larger area, which resulted in a more balanced steering behavior. Nine units had been produced by the end of 1936 and a total of 17 machines by the end of 1937. By the end of production in 1939, Slingsby had produced a total of 25 kites. Kirby kites have been chosen by many pilots for achieving the Silver C badge of achievement . For this, a gain in altitude of 1000 m had to be achieved, a 50 km target flight and a continuous flight of 5 hours had to be completed.
Competitive use
After the successful first use in 1935, two Kirby kites were used at the National Competitions in Camphill in 1936 . In addition to an award for most of the flying hours, no other noteworthy results could be achieved here.
The Nationals 1937 six Kirby participated kites, but were no longer classified as a high-performance glider. Nevertheless, two of the best flights could be carried out with kites: a cross-country flight of 125 km by JE Simpson to the coast to Withernsea and another over 128 km from K. Lingford to Easington .
Modifications
In late 1937 or early 1938, Slingsby fitted a Kirby kite with a NACA 4416 profile, which ended in a NACA 2412. This was possibly a test machine for the Type 12 Gull , which first flew in April 1938.
In 1940 most gliders were requisitioned for military use in the Royal Air Force . To find out to what extent aircraft made of wood can be located by radar , different types of aircraft were towed to 10,000 ft. With an Avro 504 and disengaged over the English Channel . It was found that a clear echo could be seen on the radar screen, which was attributed to the metal parts such as cables and bumpers. In order to eliminate this influence, all metallic control elements in a Kirby Kite were replaced by wooden bumpers, which only led to a slight decrease in the radar echo. All the kites were then assembled in Ringway , where first attempts were made to create a simulated air landing operation. The No. 1 Glider Training Squadron with initially five, later 14 with RAF standard camouflage in green / brown provided Kirby kites, then relocated to Haddenham in Buckinghamshire in January 1941 . Remaining copies were later given to the Air Training Corps.
With the end of the war, Slingsby planned to develop a modernized version of the T.6 with the T.23 . The wings remained unchanged except for spoilers that are now standard. In addition to a landing gear wheel, the fuselage received a higher pylon on which the wings were seated, which improved the aerodynamics in the fuselage-wing transition area. The pilot sat with it under the wing leading edge. The T.23 flew in December 1945, but series production did not take place because the improvement in performance was only slight.
construction
Wherever possible, Slingsby used Grunau Baby components for the wings and tail unit. Only the corners of the vertical stabilizer were rounded, otherwise this remained unchanged. As with the Grunau Baby, the wings were designed with a single spar with a torsion nose made of plywood. Behind the stile, the ribs were connected to one another with a linen band. The gap between the wing and aileron was also covered with a strip of fabric. The fuselage cross-section was composed of a semicircle above the fuselage reference line and two arcs below, which met at an acute angle like a keel on the underside of the fuselage. Because of the shoulder -wing design with the wings lying close above the fuselage, the three main ribs only required a slight increase in the cross section in the upper part. The wings of the Grunau Baby, on the other hand, were positioned significantly higher above the fuselage. A Göttingen 535 was used as a profile at the wing root, which ended in a symmetrical profile up to the wing tips.
The entire hull, built using a half-shell timber construction, is stiffened lengthways with longerons and completely covered with plywood. The cockpit has no wind protection, but has a wooden “collar” that only allows the pilot's head in the airstream.
Technical specifications
| Parameter | Data |
|---|---|
| crew | 1 |
| length | 6.21 m |
| Trunk width | 0.59 m |
| span | 14.20 m |
| Wing depth | 1.20 m |
| Wing area | 14.5 m² |
| Wing loading | 15.9 kg / m² |
| Wing extension | 13.8 |
| Empty mass | 138 kg |
| Takeoff mass | 231 kg |
See also
literature
- Martin Simons: Sling's Sailplanes, Part 6 In: Airplane Monthly. January 1993, pp. 30-34.
- Martin Simons: Segelflugzeuge - 1920 to 1945 , Eqip Werbung & Verlag GmbH, 2001 (2nd edition 2005), ISBN 3-9806773-6-2 , p. 171 ff.
Web links
- Slingsby Guide, pp. 8-11
- Photo and short history (accessed September 22, 2015)